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The iOptron MiniTower - A Second Opinion

Like
many of you, even though I have more telescopes and mounts than I can
practically use (just ask my wife), I am always in the market
for new and more sophisticated equipment. Hence, I have for some
time been looking for an automated alt-az mount to replace the
hand-operated one that I use with my 5.1-inch (105 mm) refractor, as
well as those I use with my 90 mm refractor. Having read the
favorable reviews that the iOptron MiniTower received, I decided to
purchase one and for, good measure, the iOptron Mini Cube Pro as
well. The MiniTower was intended for use at our mountain home, where
I spend a few weeks every year, and this is the story of my
experience with it. I will review the Mini Cube Pro later this
spring.

I
purchased both from a well known dealer; the MiniTower preceded my
arrival in the mountains by about three weeks. Fortunately, my wife
was here to take custody (I "forgot" to tell her about my
purchase; she thought what UPS laid on our doorstep was a roof rake).
When I arrived, the first thing I did after unpacking was, of
course, to check out the MiniTower. It came in two separate
boxes—one containing a reasonably sturdy metal case in which
the mounting head, controller, counterweight/second telescope arm and
various cables were neatly packed. The tripod and 11-pound
counterweight were packed in the second box. It was wise of iOptron
to pack the counterweight with the tripod and not with the head and
controller, either of which could have been damaged if slippage had
occurred. All of the equipment was in excellent condition.

After
removing the various components from the box, I printed the so-called
instruction manual from the enclosed mini-compact disk, and began
putting the mount together. It is no exaggeration to say that the
instruction manual is incomplete and, in at least one case,
inaccurate. Anyway, having succeeded in assembling the mount, which
requires various threading and adjustments, I added the
counterweight and locked the telescope to the assembly (my refractor
had a 1.5-inch dovetail plate attached, which seemed to work
perfectly well, even though the instructions suggest a 1.75-inch
version) and balanced it (more on that later). Then I began
programming the controller. At the appropriate point, per the
manual, I pushed “to park position,” and waited for the
motors to engage as the manual said they would. Nothing happened. So, I
manually aligned the scope in a vertical position, using a
level to ensure precision, pushed "to park position" again,
and shut the power off. Then, I breathlessly waited for it to get
dark.

Here is
a photo of the mount and telescope, properly aligned in the "park"
position:

The
“new
telescope rule” must not apply in the case of mounts, for that
evening was brilliantly clear, and I looked forward to an
enjoyable night under the stars. Once powered up, the internal GPS
quickly locate the satellites it was seeking. And in just a couple
of minutes, it locked on them. I selected the “one star quick
align” and pushed “enter.” Nothing happened,
except that the controller told me to align the star in the center of
the eyepiece and push “enter” again (I learned later that
the MiniTower, when used in alt-az, only slews to alignment stars
using the two-star alignment function). So I decided to slew the
telescope to the alignment star using the hand controller. I pushed
the “down” button and the “slew right”
button. The telescope began to slowly move down, but it did not move
in azimuth. I tightened the azimuth lock, loosened the azimuth lock,
and unmounted and remounted the head, but it would not budge in
azimuth. I took the mount inside, tried a different power source and
a warmer climate, but it would not move in azimuth. Finally,
I loosened the azimuth lock and manually swiveled the head to
and fro several times, tightened the lock, and once again tried to
slew it electronically. It jerked a couple of times to the
right, then stopped. That was it—there was no more movement in
azimuth. The mount was obviously defective.

Here
are
photos of the various knobs that require tightening, including the
azimuth lock:

I
telephoned the dealer the next morning. To the dealer’s
credit, they agreed to send me a new one without further delay, as
well as a UPS prepaid return slip. The new MiniTower arrived in a
few days.

Assembling
the new mount was much easier, since I was familiar with the process. I
should note that, once again, the mount arrived well-secured and
well-packed. Following setup, I turned on the power and tried
slewing. Hooray! It slewed freely in both altitude and azimuth. But
slowly. To adjust the slewing speed, I looked for the "speed"
button described in the manual, but it was nowhere to be found. It
turns out that there is no speed button, and that the slewing speed
is adjusted by simply pushing one of the number keys.

And as
luck would have it, a clear night was once again in store. Wanting
to be sure that nothing went wrong this time, I very carefully
balanced the telescope by loosening the altitude lock, picking a
mid-weight eyepiece, extending the focuser to a typical length,
loading the finder, and extending the dew shield. After a few
adjustments, the scope balanced perfectly, and I tightened the
altitude lock.

At
dusk,
I powered the mount up and waited for the internal GPS to locate
satellites. After waiting for what seemed to be forever, I gave
up and slewed the telescope to the west, where the two-day-old
crescent moon and a brilliant crescent Venus were setting side by
side—large crescent and small crescent, both with horns pointed
skyward. I watched this magnificent sight for about 40 minutes
until the planet and moon were so low on the horizon that the view
was no longer good, then shut the mount down, and went in for dinner.

After
dinner, I decided to try the MiniTower on stars and deep-sky
objects. I powered it up once again and waited for it to find
satellites. Waited and waited. After what again seemed like an
inordinate amount of time, I decided to go in and read a book
while it was searching. Finally, after about 25 minutes,
I returned
and found that the satellites had been located. Wondering why it
took so long and recalling that the previous mount had not only
quickly located the satellites but, once locked in, when turned off
and back on, found them instantly, I decided to test the mount.
That was a mistake. Twenty-five minutes and a few chapters
of my book later, it again located the satellites.

Using
a 27 mm Panoptic eyepiece (22.6x), I slewed to the
alignment target, pushed “enter,” and voilà, the
mount was aligned. I then slewed to a number of other
winter sky targets and found that the “go to” feature of
the MiniTower is quite accurate. In every case, the object was
within the field of view up to 27 mm eyepiece. I did notice
that the mount had a tendency to slew clockwise much more often than
counterclockwise. Hmmm. A Problem? Anyway, I decided to
change eyepieces, moving from a the Panoptic to a 6 mm Radian,
together with the requisite 1.25 mm. adapter. I had no sooner
attempted to place the smaller focal length eyepiece into the adapter
on the telescope than the alt clutch slipped, causing a loss of
alignment. Angry, cold and frustrated, I retired for the night.

The
next
day, I did extensive Internet research and found very much
opposing views concerning the MiniTower. Some owners say it is
terrific; others have had problems. One noted problem was with the
azimuth gears; another with the GPS. Various website entries
explained how to fix the GPS. But rather than risking receipt of bad
advice from the Internet, I called iOptron and talked with a nice
technician, who verified the recommended fix—remove the top
plate and be sure all electrical connections are in fact connected,
and when they are, jiggle the wires. I did that, replaced the
top, repowered the mount, and the GPS worked to perfection. I also
asked the technician about the slipping of the vertical axis clutch.
This was on a Friday. He said he would have to check with someone
and would call me back on Monday. As I write six days later, I have
still not heard back from iOptron, despite my having left a reminder
message on Monday.

But
once
again, a clear night was in the offing, and when darkness
arrived, I repowered the mount, aligned it, and slewed around to
a number of objects. Once again, the “go to” was
very accurate. However, the mount continued to slew far more often
in a clockwise direction, and the power cord ultimately became fully
wrapped around the mount head. Yup, a problem. How to undo it? Two
choices: slew the mount counterclockwise three or four times using
the hand controller or disconnect the power and unwind the cord,
reconnect the power, and realign the mount. This is something that
iOptron really needs to address.

Next,
I decided to see if Rigel’s companion was visible and
moved the scope to that star and put on power, using a 3 mm. radian
(203.3x). No alt slip this time, perhaps because I tightened the alt
lock with as much strength as my weak arms could muster, or perhaps
because I was very careful. To my surprise, having only used the 27
mm. panoptic previously, the image jumped around the Radian's field
of view. At first, I thought the tripod might be unsteady (some
Internet commentary questioned the stability of the iOptron-supplied
tripod). But that was not the case. Mounted on anti-vibration pads
(the MiniTower has neat little rubber feet that fit perfectly into
the pads) and properly secured, the tripod was quite steady indeed. No
room for criticism there. As the mount made a humming and
then bumping, and then humming and then bumping, noise, I next
suspected that the problem might lie in the gears. However, by this
time Rigel was not high in the sky, and I also thought that it
could be the atmosphere (seeing in the mountains is often not good,
particularly as objects fall down from the zenith). So, I shut
the mount down and again retired.

Note
the
anti-vibration pad:

The
succeeding night also began clear, and I decided to further test
the steadiness of the mount under power. I slewed the scope to
the moon and again, using a 3 mm. radian, saw the moon jump around in
the field of view. Obviously, something was wrong. I also
noticed that when using the controller at speeds of 64X, 16X, 8X,
etc., rather than slewing smoothly, the mount jumps across the sky. And
so, I was disappointed. Both the sky and my mood turned
cloudy, so I packed the scope, mount and accessories up

Before
concluding, I must confess to being a gadget geek and a bit of a
perfectionist. Much of my equipment is high-end, and I like things
to work properly.

The
bottom line? The iOptron MiniTower has enormous possibilities, but
the two I received were not up to par. If the MiniTower worked
properly, it would be a bargain at the price offered. iOptron
gives a good two year warranty on its products. However, iOptron
appears to have quality control issues. I am advised that the
problems I experienced are readily repairable and could have
been caught prior to delivery to the dealer. It would be worth this
young company's while to invest in better quality control and,
perhaps, individual unit testing. While that might add a few dollars
to the cost of the product, most astro-consumers I know would rather
pay a little extra for something that was relatively certain to work
properly. In any event, while the mount may be marginally suitable
for visual use (or even better, depending upon your level of
tolerance and the quality of the particular unit you receive),
I do
not recommend it for astrophotography.

Corollary: I learned that Steve Forbes operates a company in
New
Hampshire called Trapezium Telescopes & Services that regularly
services iOptron products and has developed an upgrade that, for a
fee, may cure the problems to which I have referred. I had
a lengthy talk with Steve; he is going to lend me one of his
“fixed” iOptron MiniTowers so that I can compare it
to the two I received. I will supplement this review with
the results of that test.